In general, a fiber optic transceiver is a communications device having an optical interface and an electrical interface. The optical interface transmits and receives fiber optic signals (e.g., through a set of fiber optic cables). The electrical interface transmits and receives electrical signals (e.g., through a circuit board connector mounted to a printed circuit board or PCB).
Ten Gigabit Ethernet Small Form-Factor Pluggable (XFP) is a standard “off-the-shelf” fiber optic transceiver package often used for IEEE 802.3ae Ethernet communications. The electrical interface of an XFP module operates according to an XFI protocol, and has a thirty-pin electrical interface. An XFP edge finger socket may receive and mate with an XFP edge finger connector.
Small form factor pluggable (SFP or SFP+) modules are also standard “off-the-shelf” fiber optic transceiver packages which are optimized for high-speed fiber optic channel applications. Both SFP modules and SFP+ modules include electrical interfaces and have twenty-pin electrical interfaces which plug into a small form factor (SFF) host connector. The electrical interface of an SFP module may operate according to an SFP protocol such as Serial Gigabit Media Independent Interface (SGMII). The electrical interface of an SFP+ module operates according to the SFI protocol. In general, the physical form factor of an SFP or SFP+ fiber optic transceiver is smaller than an XFP fiber optic transceiver.